Hi Guys,
I'm quite new to the whole boombox scene and have only just bought my first few boomboxes over the past few weeks. I have really enjoyed the site, looking at everyone else's awesome collections and learning about the various sought after boombox models. Currently I have -

Sanyo M4550K
Sharp GF-8585
Sharp GF-666

Last week I acquired a Sharp GF-9000Z which is in very good cosmetic condition and which I bought for a reasonable price. The reason the price had been reduced is because the left speaker wasn't functioning. I have opened the box up and done a little troubleshooting of my own. So far this is what I have discovered -

- The left tweeter still works so it is probably not a problem with the left channel of the amplifier.
- The wiring to the left woofer all looks fine. However I did also disconnect the speaker wiring running to the right woofer and connected these wires to the left woofer and it still did not function.

So at this stage I'm pretty sure the left woofer is dead. I would still like to get hold of some other speaker which I can hook up the left channel just to confirm the speaker is definitely dead. But what are my options for getting this boombox working again?

I have heard of companies which "re-coil" old speakers which are no longer working but I would think this would be quite expensive. I have looked at some replacement 8" woofers but all of them seem to be 8ohms which won't suit the boombox as I believe the existing speakers are 3.2ohms. If I was also to replace the speakers with some new one's I would most likely have to try and hunt down some which don't have huge magnets to clear the circuit board and the box would likely require some modification to fit them.

So I'm basically wondering what people think I should do? Does anyone by any chance have a Sharp GF-9000 woofer in their spare parts? Any help and advice is greatly appreciated, Cheers Benny

Long shot, but just check the copper wire connecting the speaker terminal to the coil hasn't come adrift from the solder point. (Unlikely in normal use) but stranger things have happened....

Did you check the woofer terminals for continuity? You should be reading somewhere around 3 ohms, +/-.

If that doesn't work, then just replace the woofers with some automotive woofers. Home audio woofers are indeed 8 ohms typcial. However, car audio speakers are often 4 ohms, which will replace your current speakers just fine. BTW, are you sure the woofers are 8 inchers? I have seen speaker sizes vary and a 6-1/2 inch speaker could measure 7-1/8 from flange to flange. One source for speaker drivers is partsexpress.com, however, I don't know if they will be willing to sell internationally. I believe you will find something that will work. Just remember to replace them in pairs and choose a set with high SPL sensitivity. Portable gear doesn't have enough headroom to drive inefficient speakers and produce satisfactory volume.

I have removed the speaker completely since my last post and have checked the copper wires connecting the speaker terminal to the speaker coil and they seem fine.

I don't have a multimeter with me so I will have to wait until I get home to be able to test the speaker continuity with a multimeter or see if I can borrow one off of someone. As far as the woofer being 8" in size and if you see the post by "fuzzyduck" in the thread here which shows the specifications of the Sharp GF-9000 it states 2 x 20cm woofers (which is equal to 8") -
http://stereo2go.com/eve/forum...971018973#5971018973

I have also taken this photograph of the speaker -



As you can hopefully see from the image, the outside measurement is 205 millimetres or approximatelly 8.2 inches and the inner measurement is 174 millimetres or 6.96 inches.
Thanks for the help so far, Cheers Benny

I also checked out partsexpress.com. They do have a good range of woofers in 8" and 4 ohm impedance however I think that postage will be a real killer to Australia.

**EDIT: I just checked it out and I have to have a minimum order of USD$50.00 on partexpress.com and postage to Australia will be about USD$80.00 so it ends up being pretty ridiculously expensive.**

From what research I've done 8" woofers in a 4 ohm impedance don't seem to have a great availability in Australia. Anyway these are the woofers I picked out from parts express, what does everyone think would be the best one -

http://www.parts-express.com/p...m?Partnumber=290-272

http://www.parts-express.com/p...m?Partnumber=290-312

http://www.parts-express.com/p...?Partnumber=290-356#

http://www.parts-express.com/p...m?Partnumber=290-310

http://www.parts-express.com/p...m?Partnumber=299-270

http://www.parts-express.com/p...m?Partnumber=299-246

Cheers Benny

Looking at the specs alone, I would personally go with the Goldwoods (2nd one). However, your choice is probably going to be limited to what can fit. The diameter is only one part of the equation. The depth may be too much for your application. Don't pick the last woofer -- it only goes to 2khz and is probably better suited for a sub/deep bass driver or 3 way application where a midrange is employed. The Goldwood goes to 7khz. For the most part, full range drivers would work best since most boombox tweeters are pretty crappy to begin with and a deep bass will probably leave the sound pretty dull, without much sparkle.

Oh yeah, and one more thing. If you don't have a multimeter, don't worry. A simple 1.5 volt battery (or even 9v if you are careful) can be used. With a short wire twisted around one terminal, place one end of the battery on the other speaker terminal and quickly drag the wire across the other battery terminal. If the speaker is working, you'll get a loud crackle. If you get nothing, then the speaker is dead. That is a quick, dirty, but very effective way to confirm speaker viability. Again, just give intermittent current to the speaker. Don't connect the battery and hold it. Continuous DC current is NOT good for speakers.

I just tried the battery trick and there was no sound at all coming from the speaker, so it looks like it is definitely dead.

As far as the replacement speaker goes, the mounting depth of the original speakers is around 83-84 millimetres which is only about 3.36 inches. So they are very shallow, whereas those Goldwood woofers have a mounting depth of around 92.5 millimetres or 3.7 inches. So I may have some clearance issues with those.
However postage from partsexpress.com is so expensive for me anyway that I would be better off if I could find something in Australia. However with all my looking I haven't been able to find a well priced 8" woofer which has an impedance of 4 ohms.

You can use 8 ohm speakers with no problems. It just won't be as loud. Might not be cheap to buy via airmail but I think I'd prefer that to a dead channel. The mounting depth might be a problem but you'd really need to see it in the chassis to see if you have the clearance. The difference between the 2 speakers is only 8-9mm, which isn't that much. Check the clearance first of the speakers mounted in the chassis. Also, I don't know if your originals are surface mounted or back mounted but if back mounted, is it possible to surface mount it? That will give you an additional 1/2" clearance, at least.

Hello benny,i`m not sure how oz is with aiwa hifi`s,wether aiwa hifi`s are popular or not over there,but i have a GF9000,i also have a pair of aiwa Z9400 speakers,they have 8" bass speakers in them,also,if you can get ahold of a bad Crown Sz5100 Ghetto blaster,they have "8 bass,and i can also tell you that if you can get hold of a pair of Amstrad speakers (not sure you got amstrad in oz) but the cheapo amstrad speaker that went with the old stacking hifi,they have 8" bass in them aswell,oh and the outer rims of all i mentioned,are not the square rim,they all have the "all round rim" that match the origonal 9000 bass which the 9000 has to have to fit properly,if it helps i can take a foto of all the 8" that i have,so at least it will give you an idea for a cheaper alternative that you can look out for down your way...

Stormin Normin, yeah the original speakers are surface mounted so wouldn't be able to get too much more clearance there. I'll have to get some more accurate measurements so I know how big a speaker in terms of depth and magnet size I can safely fit in there.

Thanks for those tips gettoman, I'll keep an eye out if any of those systems come up. As far as Amstrad speakers go I haven't heard of them and searches in Australia didn't yield much so not sure if they are available over here. However some pictures of the 8" you have would be greatly appreciated in my searches.

I would obviously prefer to fit a 4 ohm speaker so I'll see if I can find anything locally before I think about spending a couple of hundred US dollars on getting some woofers from parts express. Anyway thanks for all the help and advice guys, it is greatly appreciated. Cheers Benny

Hello benny..here you go..

Amstrad speakers...old and cheap,have 8" woofers..
http://img16.imageshack.us/i/dsc01214m.jpg/

http://img14.imageshack.us/i/dsc01215g.jpg/

http://img34.imageshack.us/i/dsc01216u.jpg/

if you can get a bashed in one of these..8" woofers..
http://img12.imageshack.us/i/dsc01217a.jpg/

http://img193.imageshack.us/i/dsc01218we.jpg/

or if you can buy a pair of these aiwa Z9400 speakers..8" woofers,i know someone with an M90 with a set of these in,sounds nice..
http://img34.imageshack.us/i/dsc01219m.jpg/

http://img200.imageshack.us/i/dsc01220sa.jpg/

Thanks for those pictures gettoman, they will definitely be useful in my search.
I did locate an Aiwa Z9400 on eBay Australia, however it is the whole hi-fi system so they are looking for $1000.00 for the lot, so a bit expensive. I'm also gonna get some quotes on having the speaker rebuilt this weekend, so I'll see how much that is. Thanks again for all the help everyone, Cheers Benny

Hi Benny

If you're still stuck send me a pm, I have some contacts and ideas. I'm in Victoria and have had to do this numerous times, good luck!



Rock On.

That would be awesome Gluecifer, PM sent. Cheers Benny